chore: bump authlib from 1.6.0 to 1.6.4 in /services/mcp-server

Bumps [authlib](https://github.com/authlib/authlib) from 1.6.0 to 1.6.4.
- [Release notes](https://github.com/authlib/authlib/releases)
- [Changelog](https://github.com/authlib/authlib/blob/main/docs/changelog.rst)
- [Commits](authlib/authlib@v1.6.0...v1.6.4)

---
updated-dependencies:
- dependency-name: authlib
  dependency-version: 1.6.4
  dependency-type: indirect
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]